The invention relates to the elimination of hydrogen sulphide from natural gas, crude oil, and mixtures thereof.
It is well known that crude oil or natural gas frequently contains considerable amounts of hydrogen sulphide. Since hydrogen sulphide has a strong corrosive effect on the equipment with which the natural gas or crude oil comes in contact, and is, moreover, highly toxic, it must be eliminated. The elimination of hydrogen sulphide from natural gas using acetic acid and hydrogen peroxide in the presence of a catalyst is already well known. In this method, it can be assumed that peracetic acid is the active reagent, as it is formed from acetic acid and hydrogen peroxide under the conditions described in the prior art. It is also known that other organic per acids can be used to eliminate hydrogen sulphide from gaseous hydrocarbons. However, complete elimination of the hydrogen sulphide was not possible. It is also known that injecting hydrogen peroxide together with an alkali or alkaline earth hydroxide into geothermal steam will reduce the hydrogen sulphide content. But again, complete elimination of the hydrogen sulphide has not been accomplished in this manner. From EU-AS No. 29, 472, it is also known that liquid hydrocarbons can be treated with an aqueous solution of hydrogen peroxide and a metal ion catalyst such as iron (III) chloride and copper (II) chloride, to eliminate sulphur compounds.
In contrast to the prior art, the object of the invention is the development of a process for the simple elimination of hydrogen sulphide from natural gas and crude oil or mixtures thereof, which will require neither catalyst nor organic additives, while permitting the complete elimination of hydrogen sulphide from the hydrophobic gaseous or liquid phase. Furthermore, the inventive method can be carried out under the conditions which frequently occur in the extraction of natural gas or crude oil from the ground.
The object of the invention is accomplished in a process for the elimination of hydrogen sulphide from natural gas, crude oil and mixtures thereof, which is characterized in that an aqueous hydrogen peroxide solution is added at elevated pressure and, in some cases, elevated temperature to the watery natural gas, crude oil or mixtures thereof pumped from the ground; and reacted in a reactor with mixing and with the maintenance of the elevated pressure, at least until the desired reduction of the hydrogen sulphide content is complete.